642447650240 has 112 divisors (see below), whose sum is σ = 1670685938784. Its totient is φ = 233367859200.

The previous prime is 642447650231. The next prime is 642447650249. The reversal of 642447650240 is 42056744246.

It is an interprime number because it is at equal distance from previous prime (642447650231) and next prime (642447650249).

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 642447650191 and 642447650200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642447650249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3215342 + ... + 3409298.

Almost surely, 2^642447650240 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642447650240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (835342969392).

642447650240 is an abundant number, since it is smaller than the sum of its proper divisors (1028238288544).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

642447650240 is a wasteful number, since it uses less digits than its factorization.

642447650240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194926 (or 194916 counting only the distinct ones).

The product of its (nonzero) digits is 1290240, while the sum is 44.

The spelling of 642447650240 in words is "six hundred forty-two billion, four hundred forty-seven million, six hundred fifty thousand, two hundred forty".